• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.37 no.3
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• pp.23-32
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• 2005

A change of z-directional structural and surface properties by calendering has a great influence on liquid penetration into a sheet. It could be also important for multi-ply sheet because it contacts liquid dunhg coating or converting process. Therefore, this study was aimed to evaluate of a change of z-directional structure in multi-ply sheet by calendering. To do this, multi-ply sheets were prepared with various raw materials and calendered at the different pressure and temperature conditions. In multi-ply sheet which consisted of one kind of pulp fiber, thickness reductions were higher in top and bottom plies than in middle plies. And in the case of soft nip calender treatment with high temperature, top layer which was in contact with heating roll showed the highest reduction of thickness. Hard nip calender treatment showed U-shaped density profile in z-direction, but compression profile by SNC treatment was dependent on calendering condition. To examine z-directional structure of multi-ply sheet which was composed of different raw material for each layer, CLSM (Confocal Laser Scanning Microscopy) analyses were carried out on cross direction of sheet. It turned out to be a useful tool for investigating z-directional analysis. As a result, variation of thickness reduction in z-direction is dependent on ply structure, compressibility of pulp fiber, and calendering condition.

• Proceedings of the SAREK Conference
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• 2006.06a
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• pp.897-902
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• 2006

Natural ventilation is an effective method for improving IAQ(Indoor Air Quality) and removing heats in buildings. In oder to use natural ventilation, many factors such as wind pressure around the buildings and possibility of air intake on different shapes need to be known. On this paper, the natural ventilation performance in multi-housing units of tower-type buildings was investigated. Tower-type multi-housing buildings are recently more and more constructed for they may change urban landscape and get more openness in multi-housing site. However, such housing buildings have problems with natural ventilation because of the various directions of the building units. The purpose of this paper is to find the proper building direction regarding to wind direction in order to optimize air intake in every units in the building.

• The Journal of Korea Robotics Society
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• v.13 no.1
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• pp.63-71
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• 2018

This paper describes a study on posture control of the multi-legged biomimetic underwater robot (CALEB10). Because the underwater environment has a feature that all degrees of freedom are coupled to each other, we designed the posture control algorithm by separating each degree of freedom. Not only should the research on posture control of underwater robots be a precedent study for position control, but it is also necessary to compensate disturbance in each direction. In the research on the yaw directional posture control, we made the drag force generated by the stroke of the left leg and the right leg occur asymmetrically, in order that a rotational moment is generated along the yaw direction. In the composite swimming controller in which the controllers in each direction are combined, we designed the algorithm to determine the control weights in each direction according to the error angle along the yaw direction. The performance of the proposed posture control method is verified by a dynamical simulator and underwater experiments.

• Journal of the Korean Society of Hazard Mitigation
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• v.6 no.3 s.22
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• pp.37-45
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• 2006

In this study, displacement ductility capacity and plastic hinge regions of reinforced concrete multi-column bent with different transverse reinforcement ratio are investigated. The ductility increases remarkably as transverse reinforcement ratio increase and the multi-column bent loaded along transverse direction is more ductile. The plastic hinge length for special detailing requirements of transverse reinforcement is estimated. For high target ductility, plastic hinge length for confinement should be extended with increased transverse reinforcement ratio. The plastic hinge length of multi-column bent loaded along transverse direction is shorter than that along longitudinal direction, because of the different moment distribution.

• Kyungpook Mathematical Journal
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• v.55 no.4
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• pp.1053-1067
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• 2015

A two-direction multiscaling function ${\phi}$ satisfies a recursion relation that uses scaled and translated versions of both itself and its reverse. This offers a more general and flexible setting than standard one-direction wavelet theory. In this paper, we investigate how to find and normalize point values and derivative values of two-direction multiscaling and multiwavelet functions. Determination of point values is based on the eigenvalue approach. Normalization is based on normalizing conditions for the continuous moments of ${\phi}$. Examples for illustrating the general theory are given.

• 제어로봇시스템학회:학술대회논문집
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• 2003.10a
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• pp.156-161
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• 2003

It is an interest problem to predict substance distributions in three-dimensional space. Recently, a research field as Geostatistics is advanced. It is a kind of inter- or extrapolation mathematically. Some useful means for the inter- and extrapolation are known, in which slide window method with neural networks is hopeful one. We propose multi-dimensional extrapolation using multi-layer neural networks and the slide-window method. The multi-dimensional extrapolation is not similar to one-dimension. It has plural algorithms. We researched line predictors and local-plain predictors I two-dimensional space. The both predictors are equivalent; however, in multi-dimensional extrapolation, it is very important to find the direction of predictions. Especially, since the slide window method requires information to predict the future in sampling data, if they are not ordered appropriately in the direction, the predictor cannot operate. We tested the extrapolation for typical two-dimensional functions, and found an excellent character of slide-window method based on local-plain. By using the method, we can extrapolate the function until twice-outer regions of the definitions.

• Journal of the Korean housing association
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• v.10 no.2
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• pp.165-173
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• 1999

Around campus, one-room type multi-family houses have been built for more than any other types of one-room type dwelling units. However, these houses are built in a very small scale and have insufficient facilities due to the limited capital invested by the owners of the houses. Consequently, one-room type multi-family housing are lack of consideration and care for various dwellers. This study examines the existing condition of one-room type multi-family housing around campus and analyzes the data collected from the interviews and analyses of the floor plans of the housing. Finally, based on the findings from the analyses this study suggests the future direction for the planning of one-room type multi-family housing.

• Journal of the Korean housing association
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• v.23 no.3
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• pp.29-42
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• 2012

It is common that most countries focus on the development of their capital cities. As a result, other areas do not develop as well as capital cities. Some areas even develop into a kind of distressed community. This leads to the outflow of population and also difficulties for remaining people in these areas. Under such social background, international marriages are on the increase in rural areas and small and medium-sized cities, causing many problems in connection with that. Many researches on multi-cultural families had been conducted recently, but most of them approached their studies from the viewpoint of social welfare. The physical, economical and cultural environments of multi-cultural families are closely connected to each other. Therefore it is necessary to study these families from a holistic point of view. Therefore the purpose of the research is to study the living conditions and the potential needs of married female immigrants in an in-depth and holistic way. The direction of residential planning for multi-families is also provided. To do that, there are three stages of the research which are theoretical review, preliminary survey and main survey. Methods of literature review, workshop, and questionnaire are used. Based on the results of the research, recommendations for the direction of multi-cultural families residential planning are provided. Physically, living-room, bedroom, kitchen and toilet should be adjusted based on their needs. Socially, the feelings of alienation and exclusion should be reduced for married female immigrants. Economically, it is necessary to find a way to make sure that the second generations of multi-cultural families do not inherit poverty from their parents. Culturally, it is important to consider the different needs of immigrants and to embrace their own culture.

• The Journal of Korea Robotics Society
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• v.12 no.2
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• pp.228-238
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• 2017

The CALEB10 is a multi-legged biomimetic underwater robot. In the last research, we developed a swimming pattern named ESPG (Extended Swimming Pattern Generator) by observing diving beetle's swimming actions and experimented with a positive buoyancy state in which CALEB10 floats on the water. In this paper, however, we have experimented with CALEB10 in a neutral buoyancy state where it is completely immersed in water for pitch motion control experiment. And we found that CALEB10 was unstably swimming in the pitch direction in the neutral buoyancy state and analyzed that the reason was due to the weight proportion of the legs. In this paper, we propose a pitch motion control method to mimic the pitch motion of diving beetles and to solve the problem of CALEB10 unstably swimming in the pitch direction. To control the pitch motion, we use the method of controlling additional joints while swimming with the ESPG. The method of obtaining propulsive force by the motion of the leg has a problem of giving propulsive force in the reverse direction when swimming in the surge direction, but this new control method has an advantage that a propulsive moment generated by a swimming action only on a target pitch value. To demonstrate validity this new control method, we designed a dynamics-based simulator environment. And the control performance to the target pitch value was verified through simulation and underwater experiments.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.21 no.2
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• pp.131-136
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• 2008

The transducer for multi-directionally movable ultrasonic motor having lambda shaped vibrators has been proposed and designed. The two branches cross at a right angle with each other at the tip. FEM analyses of lambda shaped transducer were carried out to find vibration modes for ultrasonic motor. The lambda shaped transducer has one symmetric mode and two anti-symmetric modes. The symmetric mode generates the normal direction motion of the tip. The lateral and vertical direction motion of the tip are excited by two anti-symmetric modes. The normal and lateral direction motions made an lateral elliptic trajectory. And the normal and vertical direction motions made an vertical elliptic trajectory normal to previous one. The transducer with 1 mm in thickness and 25 mm in length has been fabricated and evaluated. The resonance frequencies of the transducer was 32 kHz and 103 kHz. The tangential and vertical vibration displacement of the transducer having the lateral elliptic trajectory were $1.5{\mu}m\;and\;1.1{\mu}m$, respectively at the driving voltage of 100 Vpp and frequency of 32 kHz and 103 kHz. And the tangential and vertical vibration displacement of the transducer having the vertical elliptic trajectory were $0.4{\mu}m\;and\;0.2{\mu}m$, respectively at the same driving condition.